Mercer County is in Great Lakes & Wilds Pennsylvania. Of the 67 counties in the Keystone State, Mercer County ranks 33rd in terms of size (682 square miles). Mercer County, Pennsylvania, has roughly 1,000 acres of farms for sale based on recent Land Network data. The combined market value of land and rural real estate for sale here was almost $5 million. The average price of farmland for sale in Mercer County was $369,607. Farms for sale in Mercer County support livestock including horses, cattle, pig, sheep and goats. Browse all Pennsylvania farms for sale on the Land Network to find the farm, cattle operation, hobby farm or other farm property that's right for your future business or lifestyle needs.